The correct answer is:
On the other hand.
"He looked forward to visiting with old friends. Greta, on the other hand, dreaded seeing her old boyfriend."
This phrase is showing Greta and Fred are having different feelings in that moment, creating a contrast between both of them.
Alrighty, so, you're currently trapped inside a cottage with a witch who wants to eat you and your brother. What do you do to escape? Do you beat the witch with her own broom and make a run for it? Do you push her into the oven (This is what happens in the story) and lock her in so that she burns up, then you and Hansel make a great escape? What do you do? (:
Using an absolute adjective in a comparative sentences makes your English sound strange so watch out! Another example of an absolute adjective is 'unique' because it means 'one of a kind' and, therefore, it can not be 'more unique' than something. It's either 'unique' or it isn't.
A conjunction is a word used to connect words or group of words.
A coordinating conjunction joins words or group of words that are similar. They connect words and phrases and also independent clause to form compound sentence.
so the coordinating conjunction in this sentence would be and